- [Voiceover] Inflammatory bowel disease
is a chronic inflammatory disease, as its name suggests.
And both types of the disease, both Crohn's disease
and ulcerative colitis, usually last throughout one's life
after they're diagnosed.
And if they're not properly managed, they can result
in many serious or potentially
even life-threatening complications.
So, let's briefly talk about the clinical course
of inflammatory bowel disease and how it relates
to treating IBD.
So let's create a timeline of the severity
of inflammatory bowel disease.
So, on the X axis, we have time,
so this is going to be over a period of years to decades.
And then, on the Y axis, we'll have the severity of disease.
And we'll classify the severity kind of in three
categories here, with mild, moderate, and severe.
So, you'll notice that early on in the disease process,
it starts out fairly mild.
In fact, during this period, someone may not necessarily
realize that they have inflammatory bowel disease.
But then, it's going to spike.
And these spikes are known as relapses or IBD flares.
And it's during this first inflammatory bowel disease flare
typically when the disease is diagnosed.
But then it's treated, and the severity goes back down,
and it will go back down close to, hopefully,
close to their baseline severity.
But what you'll notice is, over time, there'll be more
and more of these flares and relapses.
And occasionally, when the relapse resolves, the severity
of the disease, the new baseline, gets worse and worse
over time.
So, these peaks are known as flares or relapses.
And then these valleys, these baseline periods,
are known as remissions.
So, this disease pattern is known as relapsing-remitting.
And it's very characteristic of both types
of inflammatory bowel disease.
But how does this all relate to the treatment
of inflammatory bowel disease?
Well, there are three goals to the treatment
of inflammatory bowel disease, and they have to do
with these relapses and remissions.
So, the first goal is to induce remission.
The second goal is to maintain remission,
or you can think about it as preventing relapses.
And the last goal is to prevent and treat complications.
Now, to understand how we can accomplish these goals,
I think it's helpful to think about the mechanism
of inflammatory bowel disease as having three steps.
And the first step is the immune response.
And this is a drawing of a macrophage, which is one
of the main types of immune cells
in inflammatory bowel disease that causes the inflammation,
which is the second step in the mechanism.
Then, it's the inflammation that results
in the complications.
Now, we can use these three steps as a framework
to develop a better understanding of how the different
medications used to treat inflammatory bowel disease
will achieve these three goals.
Now, it is important to note that many of these treatments
are effective for both Crohn's disease
and ulcerative colitis.
So I'm going to talk about them together.
However, the efficacy of some of the medications
may vary depending on the condition,
whether it's ulcerative colitis or Crohn's disease,
as well as it can vary from individual to individual.
Now, since inflammatory bowel disease most frequently
presents from a medical evaluation during this first
or second flare, let's start by discussing how to achieve
this first goal of inducing remission.
So, you can think of an inflammatory bowel disease flare
as this immune response kind of getting out of control,
and it results in a ton of inflammation.
And it's this inflammation that's causing all of the pain
and discomfort for someone
with inflammatory bowel disease.
And because of this, the primary mechanism by which
we can induce remission is to directly treat
this inflammation with anti-inflammatory medications.
And the type of medication that's going to be used
will likely depend on this severity here.
So, for flares that are mild to moderate in severity,
the primary anti-inflammatory medication
that's going to be used to induce remission is a group
of medications known as aminosalicylates.
Then, for moderate to severe flares, the type of medication
that's primarily used is corticosteroids.
Now, corticosteroids are very effective and powerful
anti-inflammatories, but the reason they're reserved
for some of the more moderate to severe cases
of inflammatory bowel disease is because they can have
many different side effects, and they shouldn't be taken
for long periods of time.
So, they're really only used when necessary.
And there are some other drugs that can be used
as anti-inflammatory medications
over the aminosalicylates, and corticosteroids are by far
the most common anti-inflammatories.
But this isn't the only type of medication
that can be used to treat an acute flare.
The other group of medications are known
as immunomodulators.
So, this immune response is largely mediated
by these signaling proteins that are released
by inflammatory cells such as macrophages.
And one of these signaling proteins is a protein known
as tumor necrosis factor alpha, which is abbreviated
TNF alpha, and it is one of the signaling proteins
that's responsible for the inflammation.
Fortunately, we have medications that can target
TNF alpha and prevent its effect.
So, one of the most common types of immunomodulators
used to treat an acute flare of inflammatory bowel disease
are the TNF alpha inhibitors.
Now, once an acute flare has been overcome
and the medications for inducing remission
have been successful, the next step is to maintain
that remission.
Now, fortunately, the medications used to maintain
remission are a lot of the same medications that are used
to induce remission.
However, in the induction, the anti-inflammatories
are the primary focus because it's the inflammation
that's causing all of the pain and discomfort.
During the maintenance phase, it's the immunomodulators
that are a little bit more stressed, but they're still taken
at slightly less doses often than they would be taken
during the induction of remission.
Then, another treatment category that's important
to mention during this kind of remission phase
is lifestyle modifications.
And although the effect of some of these lifestyle
modifications can be kind of small, they have been shown
to decrease the rate of relapse.
So, one of the lifestyle modifications is smoking cessation.
And this is especially important in Crohn's disease.
And another one to mention is diet.
Now, there's no evidence that certain diets actually cause
inflammatory bowel disease.
However, some foods may aggravate the symptoms
of inflammatory bowel disease and should be limited
or avoided as much as possible.
And these include things like dairy, high-fat foods,
as well as high-fiber foods.
And then, the last lifestyle modification
is stress reduction, which can be achieved
through meditation or routine exercise.
All right.
So, the last goal in treating inflammatory bowel disease
is preventing and treating complications.
So, let's start with the prevention.
And there's two main areas we focus on,
and that is infection and cancer.
So, someone with inflammatory bowel disease
during an acute flare is much more likely to develop
a severe abdominal infection.
So, sometimes, during these relapses or flares,
prophylactic or preventative antibiotics will be prescribed.
And the other is cancer, specifically colorectal cancer.
So, inflammatory bowel disease is associated with a much
higher risk of developing colorectal cancer.
Now, it's higher for both Crohn's disease
and ulcerative colitis, but it's significantly higher
much more so in ulcerative colitis.
So, anyone with ulcerative colitis is recommended
to start having a routine colorectal screening
with a colonoscopy starting eight years after
they're diagnosed with ulcerative colitis
or by the age of 40, whatever comes first.
All right.
So, we'll start with abscesses.
And what an abscess is is it's a localized walled-off
pocket of infection.
And on its own, an abscess isn't necessarily that bad
of a complication, but it has a risk of rupturing,
and if it ruptures, it can cause a life-threatening
infection of the abdominal cavity called peritonitis.
To prevent an abscess from rupturing and to treat it,
what happens is the individual will be starting
on IV antibiotics and then the abscess is going
to be drained.
And drainage most commonly is accomplished
by having a needle inserted through the abdominal wall
into that pocket of inflammation, and this is typically
done under x-ray guidance in order to make sure
that the needle gets right into the right spot.
And then, the fluid is aspirated out of the abscess,
and then it tends to heal down on its own.
The next complication is known as a fistula.
So, a fistula is kind of like a tunnel between
two structures that aren't supposed to be connected.
So, imagine in this drawing here, you have the bladder
and it's kind of right up next to a loop
of the small bowel.
Well, if that loop of the small bowel becomes inflamed
within inflammatory bowel disease lesions
such as in Crohn's disease, and that's right up next
to the bladder, well, unfortunately, over time,
that inflammation can extend through the wall
of the bladder and form this kind of tunnel
into the bladder.
So, the bladder is usually a sterile space,
and so now it's exposed to all the bacteria
and inflammation of the small intestine,
and you can get a pretty bad bladder infection.
So, fistulas are also treated with antibiotics
because of this infection risk, and then also they
typically will require surgery.
Now, there are a number of other complications
that can occur with Crohn's disease
and ulcerative colitis.
But the abscesses and the fistulas are two
of the most common.
Unfortunately, a lot of the complications
do require surgery.
So, about one-third of individuals who have
inflammatory bowel disease will eventually need
surgery for the treatment of some sort of complication.
And, unfortunately, surgery is not curative.
So, if you think once again about this three-step mechanism
of inflammatory bowel disease, the surgery really
only treats the complications.
It doesn't really affect the inflammation
or this immune response.
So, if you look at this clinical course over time,
unfortunately, surgery isn't going to affect it that much
because it doesn't focus on the underlying mechanism.
There is one exception to this, and that is
with ulcerative colitis.
So, because ulcerative colitis never extends outside
of the colon, someone who has inflammation
of the entire colon known as total colitis,
they can have a procedure known
as a proctocolectomy where their entire rectum
and colon is removed.
And this can actually be curative of ulcerative colitis
because there's no longer the large intestine
to become inflamed.
However, this is not something that's typically done
unless it absolutely needs to, because it is a very
big surgery.
So, if you can remember, the inflammatory bowel disease
is a relapsing, remitting disease.
It's caused by this inappropriate immune response
resulting in inflammation throughout
the gastrointestinal tract.
You can remember that you can use anti-inflammatory
medications or these immunomodulators to treat
inflammatory bowel disease.